Known as a ceramic electronic part, a laminated ceramic capacitor is generally classified into a simultaneous firing type and a non-simultaneous firing type.
The simultaneous firing type is usually fabricated by the following method steps: coating ceramic slurry on a stripe-shaped film to form a green sheet; printing a conductive paste on the green sheet to form a first conductive layer used for an internal electrode pattern; boring the green sheet at an interval of a unit scale; laminating the bored green sheet together with others and then attaching them by applying pressure thereto so as to form a laminated sheet; slitting the laminated sheet into a multiplicity of unfired chips by means of a dicer or a slicer; removing a binder from each of the unfired chips; applying a conductive paste on each of the unfired chips to form a second conductive layer used for an external electrode; simultaneously firing each of the unfired chips and the first and the second conductive layer; and forming at least one plated layer on the external electrode.
In case of the non-simultaneous firing type, the steps of the method are partially changed from those of the simultaneous firing type case. That is to say, after the binder is removed from each of the unfired chips, the unfired chips are fired together with the first conductive layer. Then, the conductive paste is applied on each of the chips fired so as to form the second conductive layer, which is subsequently fired to form the external electrode.
During the above-explained process for fabricating the laminated ceramic capacitor, various failures may occur to thereby produce waste materials of unfired ceramic, or scraps. For example, thickness errors, density errors, residual corrugations, and pin holes may occur in the step of forming the green sheet, thereby ending up to produce a useless green sheet, i.e., a waste material of unfired ceramic. The step of boring the green sheet coherently produces the waste materials of unfired ceramic. Further errors, such as lamination errors or attachment errors, may occur in the step of laminating and attaching the green sheets, thereby producing a useless laminated sheet, i.e., another type waste material of unfired ceramic. In addition, the laminated sheet may be erroneously slit to make a useless unfired chip, i.e., still another type waste material of unfired ceramic. After the slitting step, sludge or the like may be produced also as another type waste material of unfired ceramic.
The above-explained process or a similar one may be adapted for producing various ceramic electronic parts, besides the laminated ceramic capacitor. Regardless of what the ceramic electronic part is, however, the waste material of unfired ceramic may be produced during the process.
Traditionally, the responsibility for an adequate disposal of the waste material of unfired ceramic has been taken by the manufacturer of the unfired ceramic electronic parts. The disposal cost of the waste material of unfired ceramic, however, becomes very high because a recent rise in the demand for the ceramic electronic parts tremendously increases the amount of the waste material of unfired ceramic. Such a high disposal cost increases the fabrication cost. Therefore, a development of an efficient recycling method for the waste material of unfired ceramic can help to reduce the fabrication cost of the ceramic electronic part as well as the disposal cost of the waste material of unfired ceramic.